1. Field of the Invention
The present invention relates to a paper-sheet recognition apparatus that prevents from causing a jam of a paper sheet and a tear therein during its transportation, and more particularly, to a paper-sheet recognition apparatus with an improved configuration of an engaging portion between a base plate and a sensor, or the like, that detects a feature of a paper sheet.
2. Description of the Related Art
A paper-sheet recognition apparatus is used to recognize a paper sheet by using a sensor such as an optical sensor that detects optical features forming a light and dark pattern or a transmitted light pattern of a paper sheet or a magnetic sensor that detects magnetic features forming a magnetic pattern formed by components of ink printed on a paper sheet. The paper-sheet recognition apparatus is used by being widely mounted on a variety of laborsaving devices such as a banknote handling machine, an automatic vending machine, an automatic money exchanger, and a game-medium lending machine for a game machine. The type of the sensor includes a line sensor and a point sensor depending on a configuration of the sensor.
As an example of paper-sheet recognition apparatuses using the line sensor, a paper-sheet recognition apparatus as shown in FIG. 1 is disclosed in Japanese Patent Application Laid-open No. 2004-317463. A magnetic sensor 102 of a paper-sheet recognition apparatus 101 is the line sensor, which recognizes banknotes and securities printed using magnetic ink or the like. Stored in a housing 103 of the magnetic sensor 102 is a single or a plurality of magnetic detection devices. Moreover, the magnetic sensor 102 is provided with a hard metal cover 104 that covers a magnetic detection surface of the housing 103. The magnetic sensor 102 is supported by a stage 105. Formed in the stage 105 is a single or a plurality of convex portions 106 each of which has a shape protruding toward the side of the magnetic sensor 102, and each of the convex portions 106 is engaged with each of concave portions formed along a slope portion 104b of the cover 104 that is mounted on the magnetic sensor 102.
Consequently, a banknote M transported from one side (left-hand side in the figure) of the stage 105 along a transport direction X passes over the convex portions 106 as it is, and this does not cause the banknote M to enter into a space 107 between the magnetic sensor 102 and the stage 105 which are separately arranged from each other. Therefore, the banknote M during transportation is prevented from being jammed (paper jam).
A schematic view of a point sensor engaged in a base plate when the point sensor is used in the paper-sheet recognition apparatus is shown in FIGS. 2A and 2B. FIGS. 2A is a cross section of a point sensor cover 112 engaged in a base plate 111, and FIG. 2B is a perspective view representing a detection surface 113 of the point sensor cover 112. The point sensor is covered with the point sensor cover 112. The point sensor cover 112 has an end portion formed into a truncated conical shape, and the detection surface 113 is formed into a circular shape. The base plate 111 on which the paper sheet is placed and transported has a circular hole in which the point sensor cover 112 fits. As shown in FIG. 2A, a C-chamfering process is performed on an area of the base plate 111 around the point sensor cover 112.
In a transport path before and behind the paper-sheet recognition apparatus, a paper sheet is transported in a state in which it is gripped by transportation belts or transportation rollers, while inside the paper-sheet recognition apparatus, the paper sheet cannot be securely gripped by the transportation belts and/or the transportation rollers for transportation. Therefore, inside the paper sheet recognition apparatus, the paper sheet swings in a direction deviating from a fixed path, and the paper sheet is caught on a paper-sheet recognition sensor, which causes a jam and a tear of the paper sheet.
In the paper-sheet recognition apparatus described in Japanese Patent Application Laid-open No. 2004-317463, in order to prevent a banknote during transportation from being jammed, a convex portion that protrudes toward the magnetic sensor side is formed on the stage that supports the magnetic sensor, so that the convex portion is engaged with the concave portion formed in the cover of the magnetic sensor. However, the paper sheet recognition apparatus also has a problem that if there is a tiny tear in a banknote, because there is a space between the engaging portions, the banknote is thereby caught in the space between the convex portions, and therefore the jam of the banknote and the tear in the banknote during transportation cannot be perfectly prevented.
Moreover, in an example of using the point sensor in the paper-sheet recognition apparatus, there is also a problem that if there is a tiny tear in a paper sheet, the paper sheet may be caught in a space between the base plate 111 and the detection surface 113 of the point sensor, and therefore the jam of the paper sheet and the tear therein during transportation cannot be perfectly prevented.